‘Fundamental particles’ introduces the ultimate building blocks of matter, which include antimatter, and describes how the world can be understood in terms of around twenty different quantum fields. Most of the mass of normal matter can be explained by the energy in these quantum fields. Only a handful of elementary particles make up the world: quarks, leptons, and the force particles, which appear in the Standard Model of Particle Physics. The elementary particles get their masses by interacting with the all-pervasive Higgs field, but the dominant source of the mass of ordinary matter comes from the energy of the quark and gluon fields inside nucleons. The Standard Model is a towering achievement of science, but it is not complete.